Within our **daily** life **we come across geometric shapes** , squares, circles, triangles and other shapes that make up everything around us. Although we cannot discern it because we are used to seeing this **represented in notebooks and books** and not reflected in our daily lives, just by watching TV which is a rectangle or our **mobile phones** which is usually also a rectangle we can see it. All these geometric shapes are created **from straight lines and angles,** both flat and straight and varied to shape its image, such as an **Apple mobile phone** whose equipment has a rectangular shape (**has 4 right angles and 2 flat angles** ).

## What are right angles?

The simplest way to understand what **right angles** are is to see them as the **space that exists between two lines** which share the same vertex and giving a **total opening in degrees of 90º. **The word angle etymologically speaking comes from the Greek ” **ankulus** ” which can be translated as bent or twisted. With the passage of time **it was transferred to Latin** where it was established as ” **angulus** ” which can be understood to be translated as angle.

- Definition
- Characteristics of right angles
- How much is a right angle and how is it measured?
- Parts of right angles
- Types of angles
- Right angle triangle

## Definition

The right angle is defined as a line **with an opening of 90 degrees,** that is, sexagesimal. Within its amplitude of measurement it is also established in other units such **as π / 2 radians and also 100 ^{g} centesimals.**

It is Euclid who gives the definition of “It is an angle that occurs when a straight line that is presented on another ends up **producing an alignment between it, ****generating a** totally adjacent **angle** making its angle is right and that the line that is on she is a **perpendicular line** ”.

## Characteristics of right angles

- Right angles
**allow us to combine**to create other kinds of angles. If, for example,**two right angles**are connected on a plane we will see between them the formation of another**called flat angle,**while if we form 4 right angles on a plane we will get**another angle called perigonal**which makes up**360 degrees**. - When we look at a square we can see that it is made up of four equal and
**totally parallel**sides**,**we can understand that each of its interior angles are right, that is, 90 degrees and when all the angles are added, it gives**n the total metric measurement of the degrees that is 360 degrees.** - As is logical, right angles must never vary, and it is considered that of
**all the existing angles**this is the easiest to recognize compared to the other types.

## How much is a right angle and how is it measured?

Before knowing how much a right angle measures, **we must know how angles are measured** and for this we must use a protractor. The protractor is a tool widely used in engineering and architecture which allows to know the degrees of opening or elevation of a point.

The conveyor **has a circle shape** separated by half which is the most common because there are other models that form a complete circumference.

It has **a base where the** center **point is established,** which is aligned with the 0 degree point and all the degrees from 0 **to 180 degrees** are found throughout the arc of the circumference **.**

To know how much a right angle measures and how it is measured **, the protractor is taken and placed at the vertex point** , it is observed where the line projected on this vertex is and the number of degrees it has is determined. The to **angles straight** have an opening 90 degrees would be reflected in this way:

## Parts of right angles

For an angle to be called an angle, it **must comply with all the parts that make it up. **These are:

- A vertex or opening point.
- Two or more lines or vectors that are connected at a specific point.

## Types of angles

Apart from the right angle there are **several types of angles** that we will see below:

**Acute angles:**Are those that start from 0 degrees to ninety degrees so they cannot exceed a quarter turn.**Obtuse angle:**which measures more than 90 degrees but cannot exceed 180 degrees, that is, it is equivalent to a rotation greater than a quarter of a turn but less than a half turn.**Plain angle:**It is one that measures exactly 180 degrees, which would be equivalent to half a turn. This will always be recognized as a long straight line opposite its point of origin.**Concave angle:**They are those that measure more than 180 degrees, that is, more than half a turn.**Whole or complete angles:**They are those that measure exactly 360 degrees, that is, a whole turn.

## Right angle triangle

Within the right angles **we see different geometric shapes** that have remaining angles including squares and rectangles, there is also a **triangle** called a **right triangle** which has an **angle of 90 degrees.**